The fluorescence microscope is a microscope for observing a fluorescent light emitted from a sample of an observation target, and used in various fields such as biology and medicine.
In a case where the observation target is a protein in a cell, in order for the protein to be observed using the fluorescence microscope, the protein is marked by a fluorescent protein (hereinafter, referred to as “marker”) such as Green Fluorescent Protein (GFP), Red Fluorescent Protein (RFP), or Blue Fluorescent Protein (BFP), which is added to the protein of target using a gene engineering method or an immunological method (for example, see Patent Literature 1).
Then, an excitation light is shed at a wavelength appropriate to the type of the fluorescent protein, and the fluorescent light emitted from the fluorescent protein is observed and imaged, so that the sample is observed through the fluorescent protein. As a light source of the excitation light, a laser light source (Ar, Ar—Kr, He—Ne, He—Cd, semiconductor lasers, etc.), an ultrahigh pressure mercury lamp, a xenon lamp, or an ultraviolet LED is used.